As NASA sets about the task given to it by President Trump to return astronauts to the moon and then send them to Mars, the space agency has turned to an old technology, but with a modern twist. Nuclear rockets would be to key to getting people to Mars and even develop a transportation infrastructure from the Earth to the moon, according to a recent article in Wired.
When President John F. Kennedy made his famous speech before Congress on May 25, 1961, he famously said, “First, I believe that this nation should commit itself to achieve the goal, before this decade is out, of landing a man on the moon and returning him safely to the Earth.”
However, in the very next paragraph, Kennedy made another proposal that most people don’t remember.
“Secondly, an additional 23 million dollars, together with 7 million dollars already available, will accelerate the development of the Rover nuclear rocket. This gives promise of someday providing a means for even more exciting and ambitious exploration of space, perhaps beyond the moon, perhaps to the very end of the solar system itself.”
As the Apollo race to the moon raged throughout the 1960s, the Rover project evolved to NERVA or Nuclear Engine for Rocket Vehicle Application. The idea was to pump hydrogen through a nuclear reactor that would superheat the propellant and expel it out the other end. A nuclear thermal rocket would cut trip times to Mars from six months to a year to about three months.
The NERVA program was highly successful, having been tested on the ground several times. The project developed a flight test article before it was canceled during the Nixon administration since human missions to Mars had been deferred indefinitely.
Fast forward less than 50 years later, and Mars has been placed back on NASA’s agenda thanks to an executive order from President Trump. The space agency has returned to the idea of using nuclear energy to send cargo and people across interplanetary distances.
For about the past ten years, a research and development team at NASA’s Marshal Spaceflight Center has been looking into nuclear thermal propulsion on the cheap, using a fuel cell that is heated by electricity to explore what would go on inside a nuclear thermal rocket. As soon as President Trump tasked NASA with sending human beings into deep space again for the first time since 1972, the project went into high gear.
“In 2017, NASA awarded BWX Technologies a three-year, $19 million contract to develop the fuel and reactor components necessary for a nuclear engine. The following year, Congress earmarked $100 million in NASA’s budget for the development of nuclear propulsion technologies. And this year they got another boost when Congress added another $125 million for nuclear propulsion.”
The first human expeditions to Mars are not slated to occur until the early 2030s at the earliest, so NASA and its contractors have plenty of time to develop a modern nuclear thermal rocket and test it. The team at NASA Marshal is thinking about 2024 for the first flight test of a true nuclear rocket engine.
The idea is that the super heavy-lift rocket, the Space Launch System, would loft a spacecraft equipped with a nuclear rocket into low Earth orbit. A nuclear rocket would not be fired inside the Earth’s atmosphere for obvious safety reasons. Indeed. NASA will have to develop the safety protocols that would involve launching a cargo with a lot of fissionable material to start with.
The first flight test of a modern nuclear rocket probably would not involve a multi-billion-dollar space probe. One possibility would be to invite several universities and businesses to contribute CubeSats, small, inexpensive probes that could be blasted out of low Earth orbit and sent to various destinations in the Solar System. Further tests might send heavier cargos and even people to the Moon and, perhaps, Earth approaching asteroids.
In subsequent years a nuclear rocket would be the upper stage of the NASA SLS or various commercial launch vehicles such as the SpaceX Falcon Heavy and Starship and the Blue Origin New Glenn. The technology would open up not only Mars but the rest of the solar system to exploration. It would help to surmount the greatest barrier to space exploration, the almost unimaginable immensity of the solar system. Probes to the Outer Planets would be able to arrive at their destinations in half to a third of the time it currently takes.
Nuclear rockets will help open up the solar system as a new, human frontier.